1. Field of the Invention
The present invention relates to a radiocommunication system and, more particularly, to a radiocommunication system using time-division digital frames.
2. Description of the Related Art
In general, in places where many people work, such as large office buildings, factory sites and hospitals, many employees do their respective tasks, at different sections. Each employee is engaged in a task with a transceiver, so that he or she may make contact with another employee, or the office, to exchange information if needed.
In such places, not only speech communication but also communication of digital data, such as image data, is frequently performed. Speech communication can be performed by transceivers carried by employees. On the other hand, digital data communication is carried out using communication equipment such as facsimile terminal equipment, data terminal equipment or computers, which are mutually connected through normal telephone lines or private data lines provided within office buildings and factory sites. Thus, for local communication in office buildings or factory sites, different communication equipment is needed for each type of information to be transmitted.
In the radiocommunication system of an office building or factory site, in order for many employees to communicate with a base station simultaneously, the number of required transmission frequencies must at least correspond to the number of employees. Hence, when the number of employees increases, the number of radio frequencies available in the radiocommunication system must also be increased. If the number of employees increases too much, however, the number of communication channels would be inadequate, and thus sufficient radiocommunication service could not be provided.